History

One hundred children with a diarrheal infection and eighteen healthy children between 4-10 years old participated in the study. Between July 2022 and October 2022, kids from the Baghdad and Basrah provinces visited clinics for diarrhea treatment. According to the data, a total of 73 clinical samples tested negative for S. typhi, whereas 27 samples tested positive for other bacteria. When used VITEK-2 system. Only 18 (66.7%) of the 27 stool isolates were found to be associated to S. typhi. At the end of a PCR reaction, billions of copies of a certain sequence will have been produced thanks to the ability of DNA polymerase to synthesize a new strand of DNA complementary to a provided template strand (Amplicon). All of the possible S. typhi isolates had their DNA extracted, and conventional PCR was performed on the DNA samples to amplify the specific invA gene primer. Gel electrophoresis then revealed that only 16 of the 18 samples (80.9%) produced the expected invA gene at (284 bp) DNA fragment in comparison to an allelic ladder. For 18 isolates already confirmed to be S. Typhi, molecular identification of the fliC gene was performed. Each and every isolate (100%) tested positive for the presence of this virulence gene. When compared to an allelic ladder, the existence of (366) bp bands indicated a good outcome. The iroB gene, which encodes for a protein of a certain size, was discovered by polymerase chain reaction in S. typhi clinical isolates (606 pb). Among the 18 isolates tested in the current investigation, 15 (83.3%) tested positive for the iroB gene through PCR. When IL-10 levels were measured in children with a diarrheal infection and compared to those in a control group, group A showed a statistically significant increase (7.08 ±1.34), whereas group B showed a decrease (3.41±1.08). (P 0.001).